High-frequency wave signaling system



. 29, 1946- w. P. MUELLER 4 2,410,387

HIGH FREQUENCY WAVE SIGNALING SYSTEM Filed Feb. 14, 1942 2 Sheets-Sheet 1 ATTORNEY 0d. 29,1946. w. P. MUELLER 2,410,387 1,

HIGH FREQUENCY WAVE SIGNALING SYSTEM Filed Feb. 14, 1942 2 Sheets-Sheet 2 INVENTOR BY .%A

ATTORNEY Patented a. .29, 1946 l -UNITED. "STATES HIGH-FREQUENCY WAVE'SIGNALING' SYSTE William P. Mueller, Emporium, Pal, assignor to I Sylvania Electric Products lnc., a corporation of Massachusetts Application February 14, 1942, Serial No. 430,863

This invention relatesto frequency converter circuits and in particular to circuits for heterodyne reception of ultra high-frequency signals of the order of 600 megacycles.

At frequencies of this order tuned transmission lines are preferably used as resonance cirof the associated tube electrodes and their leads have the same effect as an increase in length of a tuned transmission line without these acci dental lumped reactances. U It is a principal object of the invention topro vide tunable heterodyne converter circuits which can be operated at frequencies of the order of 600 megacycles, that is, at higher frequencies than is; possiblewith known circuits. This objective is attained without any reduction in the size or sp acing of the elements ;.used in the con r u ,I V p -I t is another principal objectof theinvention to provide two sets of tuned transmission linesfor feeding two high-frequency oscillations into the input o f a tuned double diode converter circuit, which; allows separate and independent matching With the impedances of theelements which inject the signal frequency and the local oscillator frequency. I I

I A feature of the invention relates to the design of a tuned full-wave triode detector amplifier circuit, in which the back coupling at signal and local frequencies from output to input electrodes is completely eliminated because the plates are connected in parallelwhile the grids are" fedin push-pull relation.

Y Another feature of'the invention provides the use of a special construction double triode in a full-wave beat detector circuit, which materially simplifies the attainment of the foregoing'objects a'ndfeatures of the invention. g I

'Itis afurther object of the invention to provide means for feeding'the two heterodyning or input oscillations in push pull to the platesof two diode tubesin such'a way that there is nearlyno un- 7 17 Claims. (Cl.'250'f20) desirable feedback from 2 the signal input line into the local oscillator circuit. I v

Another object of the invention is to provide means for feeding the grids of a tuned full-wave double triode detector in push pull by both heterodyning frequencies, whereby interlocking of the local oscillator with the signal frequency is sub} stantiallyprevented.

A further feature of the invention relates to a simplified signal frequency tuned input circuit for a full-Wave tuned detector tube circuit, which consists of aquarter-wave line composed of four parallel wires or rods ortubings, which are short circuited at one end and each of which is attached to the two ends of one of the two input electrodes ofthe tuned full-wavedetector tube.

A feature of the invention relates to a converter circuit using a double triode in which the two cathodes of the two triode sections are short-"cir cuited inside the envelope of the tube whereby undesirable. loading of the input circuits of the tubeis reduced to a minimum. I

The inventionwillnow bedescribed in connection with thedrawings, in which g v i Fig. l isaschematic'diagram of a tuned double diode full-wave detector circuit incorporating the invention. j

Figs-2 vand 3 are views of a diode of Fig. 1. I Fig. 4= isa schematic diagram of the full wave double triode detector amplifier circuit incorporating'the invention; I o I;

, Figs.g5 and 6,-give views of the lead connections and mount structure of the; tube which is preferably usedinthe circuit shownin Fig. 4. I 'Referring toFig; 1, the re isshown a thermionic vacuumtube of the double diode type wherein numeral I represents the enclosing evacuatedv bulb or envelope: 2 and 3 represent respectively the diode anodes or plates; and 4, 5, represent .the cathodes for the respective plates .2 and 3. It will be understood that the showing of the electrode arrangements in Fig. 1 is purely schematic and that preferably eachplate has its own cathode so that the electron stream between one cathode; and its; anode is not interfered with by, the electron stream between the'other cathode and itsanode Such a structural arrangement is'shown and described in connection with Figs. 2;and 3'ofithe drawings.

In Fig. 11', each of the cathodes is of the indirectlyheated'type comprising a metal sleeve with a coating. of emissive material on its outer surface "and with a filament or heater wire insulatingly 'supported-within the sleeve. "The cathodesleeves are directly-connected by a short metal jumper 6.

is connected to ground through resistor 14 andg'a large capacity condenser 15. Tuned transmission line IS, IT, and tuned transmission line I 8, 19 ,'arer connected respectively to the lead-ins 8; Hljand 9, I, and are in the form of parallel rigid wires or metal tubes or rods whichcan be-adj'usted as a unit in length and are maintained parallel at equal distances from one another by suitable means (not shown). The four-line conductors areequalin length andare short-circuited by a metal plate or jumper ZG at the; points 21;, 22,; 23 and 24;, soas to form a-doublequarter wave transmission linewith all the conductors extending in thesame-direction from tube I. For a detailed description of atypical; supporti adjusting and spacing arrangement for the line's' 9; reference may be had to application- Serial No. 41?;068; filed; October 30 1941i Incoming" ultra lugh-frequency signalenergy from-I source 3. l'- is applied at points 25, 26-; to the right-hand sectionofthe-tuned quarter-wave line spas to be in push-pull relation to the two diode plates i, 3, over lead-ins 8 and Ill} Local heterodyning irequencyfrom-source 32 i applied at points 2-? and '28 to the left-hand section of the; quarter-wave line; also in push-pull relation to the-plates 2 and 3 over lead-ins l and 9. The resultant intermediate frequency-in the nature of; aheter'odyne between; the ultra highfrequency signals from source3;|' and the local frequency irom source 32; istaken-ofi at points {Shndfid} that is betweenthe cathode side of the intermedi e"frequencyftuned circuit; l2, l3 and ground. Ijjh'ave found that *with this arrangement, it is possible to-rece'iveand convert ultra high-frequency signals of the-order or 600 megacycles with- 1 greatf stability and efficiency. Furthermore; the reaotances-- in the; common cathodelead I- l have no detrimental effe ctr-upon the ultra high-frequency preform'ance 'since the two halves} of} the tuned tank -circui-'t{andoscillatory system; can be: balanced with respect-re ground so-th'a-t the tw signal currents in the common cathode lead: i. e., the currentsof-the frequencyoi source 3land of source 32-; cancel each other 5 out. Thisarrangement also obviates the employment of special-filtering elements in the intermediate frequency circuit for elimination of theultra high-frequency components.-

' Thus the adjustment-of location of the coupling-pcints 25 and 26 --canbecarried out on one branch; of thetuned' signal frequency" line t6; I 1,- -leadin'gto 'd-io'de plates-2 3-,- quite independentlyof the-adjustment o-f the location of the signaL-inputpoints21} 28, onthe other branch I8 l9; Inparticulari the connecting-lines-from the two high frequency sources-3i 32, to; the diode plates'can; always be kept at adistanceat least asilarge as the distance'of thetw'o branches lfig-l'lyandila l9; from each other. 'Iihisg rend rseit po si l to, ad us the: fee n p nts, 2 2 or I the si nal: ir e e n ectio i t i emal:int rfe nce w he-cor s o n fe -irs mentetthe f d n se ih s 1 285 r t local oscillations.

The simplification of the matching adjustment above described is substantially improved by the use of a special construction of double diode tube, which i provided with two plate leads for each diode plate, the leads being arranged symmetrically with respect to each other and to the oathodes and with all the connections extending in thesarne direction from the tube. The common cathodelead-in from the two cathodes enables quency signal component as stated above.

7 The circuit of Fig. 1 can be utilized with known types of double diode tubes by providing a separation of the two-tuned quarter-wave lines for the signal frequency outside the tube as above described." However, with such conventional tube. designs, there would be introduced additional undesired lumped reactances by reason of theele'ctrode arrangement and the unsymmetrical connections of the various electrodes to their respective tube prongs. These lumped -reactances-have the efiect of reducingthe-upper frequency limit: atwhich the full wave double diode circuit of Fig. l 'c'ah be used with-satisfactoryefficiency. Accordingly, there-is shown inFigs -Zand 3; a preferredconstructionor double diodetube for achieving the best results with theci'rcuits of Fig. l.

For purposes oi simplicitythebulb of the tube isomitted from Fig: 1; which merely shows the base or header 33rofth'e'tube; this headerprefery being. of glass lathe fcrm-of-a buttonor disc as distinguished fronrthe conventional single planepress'and which is sealedto'the usual glass bulb as disclosed for example in said application Serial No. 417,068; filed Oct'ober 30; 1941. Sealed in a vacuum-type manner through the base- 33 of the bulb, and preferably equally spaced arounda circle are the various lead-in pins or prongs L, 8; 9, Hi, H,- 34 and- 35; Supported on the base 33 by means of the rectangular; mica disc spacers 35,31, are'two setsofdiodes; one diode comprising the-indirectlyheated cathode sleeve 4' with 'itscylindrical anode Z andth'e other diode comprising the indirectly heated sleeve cathode 5 and its surrounding cylindrical anode 3. The filamentary heaters for the two 'c'athode sleeves are connected'in parallel by wires 38, 39, which are connectedto the contact prongs 34, 35. It willgbe understood of course, that the electrodes of' each diode are suitably fastened or'a'nchored between the mica discs 36 and 31 in any manner'well-knownin the art so as to preservethe proper'spaced relation between each cathode and its l associated anode-and'like-f wise topreservea fixed 'space relation between thetwo'diode sections.

The two cathode sleeves i and 5 are electrically and directly connected by the shortmetal 'jumper-fi which in; turn is connected to the prong H. One end of plate 215 connected by jumper 40 to prong land the opposite end of; thissame plate is' connected. by. jumper 4! toprong 8. Likewise, one end" of' plate 3 isconnected" by jumper 42 to prong 9 and, the opposite end of platej3' is connectedby jumper43to prong 10. The variousljumpers'in addition to providing symmetrical connections to the plate ends, may

0 also serve to anchor the. entire double diode assembly against movement'witlrrespect to the bulblbase 33. It will be understood or course, that after the electrode. mount. has been assembled and. connectedlin'place, and the bulb has been ensure the base 33, the tube is subjected complete cancellation of the ultra high-freto high evacuationand an exhaust schedule such as is well-known in the radio tube art. 7 v Fig. 4 shows the invention embodied in connection-with a full-wave tuned double triode mixer tube. This arrangement has the advantage of. combining amplification with the advantages of the full-wave diode mixer arrangements of Fig.1. The tube is shown schematicallyv and includesa pair of electron-emitting cathodes .45, 41, connected by a short metal strap 48. Associated with cathode 46 is a control grid 49.and apl'ate anode 55. Likewise, associated with cathode'4l is a control grid 5| and plate anode 52. Thegrids .49 and 5! are fedin push-pull relationin the same manner as are the diode plates 2, '3, of Fig. .1.v Thus the line 55, 54 and line 55, 56, are short-circuited at their corresponding ends-by the metal plate 5'! to form a double quarter-wave transmission" line. Each of the grids is provided with apair of lead-ins 58', 59, and 65, 61, which are sealed through the glass base of the tube 45 and symmetrically arranged with-respect to the anodes-and cathodes. The ultra high-frequency signal from the source 62 is applied at the points 53, 64, to the lines 53 and 54, while the local heterodyning frequency from the source 65 is applied at the points 55, 61, to the lines 55 and 55.

The plates 55 and 52 are connected together by a metal strap 58 and are connected to one end of the tuned tank circuit comprising the high-frequency inductance 59 and condenser '55. The steady positive operating potential for the plates 55 and 52 is supplied from the terminal H of a suitable power'supply source through the resistor 12 and inductance'59. The intermediate frequency resulting from'the heterodyne of-waves from sources- 52 and 55 is take off between the points l3, 14, of the intermediate frequency circuit 59,15. The condenser, 15 in conjunction with the resistor 72 separates the A; C. component of the plate voltage from the D. 0-. component thereof. A grid leak resistor 15 and parallel connected grid leak condenser 11 are connected between the short-circuiting plate 51 and ground. By this arrangement, the various circuit elements can be easily balanced with respect to neighboring conductors or ground and the ultra high frequency component of the input signal 'is cancelled out across the points Referring to Figs. 5 and 6, there is shown in more detailed form, a preferred form of tube mount for use in the system of 'Fig. 4. The mount comprises two separate triode units cons'is 't'ing of the electron-emitting cathode sleeves 46, 41. Surrounding cathode 46 is the helically wound grid 49 which, in the well-known manner, is c'arried by a pair of metal side rods 18, I9. Su'r'rounding'the grid is the rectangular box-like platanode 55. Likewise, surrounding the oathode 4'! is the helical control grid 5| -and the surrounding plate anode 52. For purposes of simplicity,-t'he filamentary heaters for the cathodes 46 and 4! are omitted, it being understood that they are insulatingly mounted within the cathodes many well-known manner.-

Each trio'deunit is assembled'between a pair of end mica spacers 84, 8! ,which are provided with. openings in the well-known manner ,to

receive-the ends of the;cathodes, the ends of the gridside'rods and the turned over ears 82 of the plate electrodes. Thus both triodesform a: rigid .unitary construction withthe various electrodes accuratelyland. permanently. spaced by 6 means'of the members and 81., The plates 50, .52, are connected together at their adjacent opposite ends by short metal straps 83, 84. One

of thejumpers, for example jumper 83, is connected to the lead-in pin or prong 85. The two cathode sleeves 46, 41, are likewise connected to.- gether by a short metal jumper slifwhich is connected by a jumper, (not shown) to thecommon lead-in .pinxfi'i. .Preferably, the glass base 88 of the bulb has eight pins sealed therethrough and equally spaced around a circle, and the duplex triode unit is positioned symmetrically with re,- spect thereto; One end of grid 49 is connected by jumper 89 to pin and the other end is connected by jumper 9| to pin 92. Likewise, one end of grid 5| is connected by jumper '93 to .pin 54 and the otherend is connected by jumper 55 to'pin 95. The remaining pins 91,,98',"are connected to the cathode heater filaments (not shown). With the foregoing arrangement, it is:

possible to effect the symmetrical connections to the two tuned transmission lines 53, 54, and 55, 56. The tube may be plugged in to a. socket such as shown in said application Serial No. 417,068, filed October- 30, 1941, and the effective length of the tuned transmission lines may be varied as described in said application. While certain specific structures and embodiments have been disclosed, it will be understood that various changes and modifications maybe made therein without departing from the spirit and scope of the invention. V a

What I claim is: T

1. A high frequency wave converting system,

comprising a-double diode tube having the oathodes connected together with a common single lead-in, a tuned tank circuit connected between said lead-in and ground, a pair of tuned double transmission lines, one-line being connected in push-pull relation to corresponding points of respective diode plates, the other'line being connected in push-pull relation to other corresponding points of said plates, means to connect high frequency signals across the first line, means to connect a source'of local oscillations across said other line, and means to lead off aresult'ant intermediate frequency from across said tank cir-' cuit- 2.,A highjfrequency wave converting system according to claiml, in which the high frequency signal'fsource and the source of the local oscillations'are adjustably connected'to their tuned transmission lines so that the impedances of said sources are matched with respect to the termij-' natinglimpedance of said lines. '1 f 13. A' high frequency wave converting system according ,to claim 1, in which one end of said tank circuitis connected to said common cathode lead-in and the'opposite end of said tank circuit is connected through a non-resonant impedance in parallel to all the ends of said transmission lines'remote' from said diodes. 4 A high' frequency wave converting system according to claim 1,]in which all the lead-ins of the double diode tube extend in the samedirection therefrom and said pairs of tuned transmis sion lines also extend in the same direction from said tube. a 5 .---A high frequency wave converting system comprising a double diode tube having-thecath-l odes connected together, a pair of tu'nedtia'ns mission lines extending in the same direction from'the electrodesof the diode one' line'being excited push pull. by high frequency signals andiconnected. to corresponding pointson IGSPEO-i ti ve diode plates, the other line being excited in push pull bylocal oscillations. and. connected to other corresponding pointsonsaid plates, a tuned intermediate frequency tank: circuit connecting said cathodes to ground, and anon-resonant impedance network connectingto ground all the ends of said lines remote from said diodes whereby. intermediate frequencywaves across the terminals of said tank circuit: are effectivelyvcancelled out; v V V 61A high frequency wavezconverting system according toclainrl'l in which said tube is a doubleidiode having the anodes'fed in push pull respectively by said high frequency signal waves and said heterodyne waves. .7. A high frequency wave converting system according to claim 17 in which said tube is of the double triode typewithv the control grids fed in push pull respectively by saidhigh frequency sign'ali waves and by said heter'odyne waves, and in which thetuned intermediate frequency circuit is excited in parallel by the plate currents of the triodes. i v

8; In a high frequency wave converting sys tem; a double diode electrontube having a pair of electron-emitting cathodes and a cooperating pair of anodes, a pair of lead-ins for each anode connected symmetrically to different points thereof, a common lead-in for both cathodes, a tuned intermediate frequency tank circuit havingone end connectedto. said-common lead-in, and the other end connectedthroughanon-resonant impedance network andin parallel to all the lead-ins connected to said anodes.-

9;"A- high 'frequency wave converting system according to claim 8, in which thetankcircuit is connected to all said anode lead-ins through a pair of tuned quarter-wave transmission lines, anda source of high frequency signal waves is connected acrossonetuned. line and a local oscillationsource is connected: across the other tuned line. Y

10. In a-high frequency wave-converting. system, adouble diode each diode having a linear. cathode andan-anodeextending. along the cathode a pair of transmission line conductors con.-

nected attheir corresponding ends to Espaced points of one anode the other ends of said conductors beingush'ort-circuited and forming. with said anode a substantially" complete inductive lohp,;an'otherpair.of transmission line conductors connejctediat their corresponding en'ds'to spaced points'lon 'theotheranode said other pair of, con ductors jfbeingshortkcircuited at their opposite ends and forming with said other anode a come. plete inductive loop; a'tuned intermediate ireuency circuit connected at oneen'd 13013118 cathodes of said diodes; and'at the otherfendto the short-circuited ends' oi said" transmission line confductors'a source of high frequencyisignal energy connected? across predetermined .points of a'pairof 'said lines to. excitej'said anodes in push pull relation and a source of local: frequency hete jodyn'e oscill'ationsv 'qoonnec't'ed. across the L other pal offliiifesgtoi excit'egsaid. anodes in push-pull rlia OIL' Iii-a high. frequency wave-converting sys item; a double triode, each triode havinga linear transmission line conductors'connected at their correspondingends to spaced points on the grid of the other triode said other pair of conductors being short-circuited at their opposite ends and formingmith thesaid grid of said othertriode a substantially complete inductive loop, a tuned intermediate frequency tank circuit connected at one: end in parallel to the plates of both triodes and at the other end to the short-circuited. ends of said transmission line conductors, a'source of high frequency signal energy connected acrosspredetermined points of one pair of said lines feedingthe grids of the two triodes in push-pull relation, and a local source of heterodyning oscillations connected at predetermined points to the other .pair of lines and also feeding the grids of said triodes inpush-pull relation.

12. A double diode tube for ultra high-frequency conversion, comprising a pair of cathodes eachhaving a corresponding anode, a pair of separate lead-ins'for one anode and connected to spaced points on said anode, another pair of separate lead-ins for the other anode and connected to corresponding spaced points on said other anode, and a common lead-in connected to both said cathodes, all said lead-ins extending insubstantially the same direction frornsaid tube.

13. A double diode tube according to claim 12, in which the two sets or diode electrodes are interlocked as a rigid unit by insulating spacers at'opposite ends.

14. A double diode tube for ultra high-frequency wave conversion comprising pair of diodes rigidly interconnected as a mechanical unit, means to support said unit one tube header, said header having aplurality of pairsof lead-- ins sealed therein and symmetrically positioned withrespect to said unit, gll said lead-ins extending in substantially the same direction'from the electrodes of the diodes, one pair ofsaid lead-ins being connected'to opposite ends of one diodeplate,-- another pair of lead-ins beingconnected to opposite endsof the-other diode plate,- means; connecting the cathodes-of the diodes directly together and a common conn'ection from-said last-mentioned means toanother of said pins."

cathode ananode, and a grid substantially coextensiyewith-the anode; a pair of. transmission line conductors connectedrat their: corresponding ends to spaced points on the grid of one triode,

thegotherii ends of saidconductorsiibeing shortcircuited and formingsiwith the gridat substan' tiallyzcompl'ete: inductive loop; another; 1 pair 0fl5-.-,A; duplex triode tubefor ultra high-frequencywave conversion-comprising aypair of triodes ri'gidly interconnected-as a-m'echa2r -ica1:unit;

'rneans to supportsaiduniton a. tube header,-said header having a plurality of pairs of lead ins' sealed therein and all extending in substantially the same direction from the electrodes of the triodes, one pair of lead-ins being connected to opposite ends of the gridof one triode and another pair of leadflnsbeingconnected to the opposite ends of the grid of the other triode; means connecting the plates ofthe triodes directly together, a connection from the lastmentioned means toanother lead-in member; said triode units, being supported symmetrically with respect to 'all the saidlead-insand means to connect the-cathodes directly together within thetube whereby undesirable loading of the input circuits to the-triodes'isreduced to a minimum; 16.- A-double* triode-for high-frequency wave conversion comprising an envelope' enclosing "a pair of triode mounts;..means within; the envelope directly short-circuiting the platestof thetriodes, and" means also within the envelope directly" short-circuitingthe cathodes, and symmetrical lead inconnections for the opposite en'dsof each grid electrode. 17.1 In a high frequency wave converting'zsys-" ter'xg-anelec'tron tube'havingiati leastone. pair of.

push-pull input electrodes and a pair of output electrodes, a pair of tuned transmission lines, one line having its conductors connected to one set of end points of the two input electrodes, the other line having its conductors connected to the other 5 end points of each of the same input electrodes, means to apply a high frequency signal across one of the lines in push-pull relation to said 

